dropItems — GTM Variable Template for Array

VARIABLES › ARRAY

dropItems EXTENDED Array

Direct (.tpl) Apply (.tpl)

Removes the first N elements from an array and returns the rest.

---

---

Examples

Drop first 2 items▶ Try

INPUT

Array To Process: [1, 2, 3, 4, 5]
Count: 2

OUTPUT

[3, 4, 5]

Drop all returns empty▶ Try

INPUT

Array To Process: [1, 2, 3]
Count: 10

OUTPUT

[]

---

GTM Configuration

This is what you'll see when you open this variable in Google Tag Manager. Hover the icons for details.

dropItems

Read-Only Try Live

Array To Process

💾 The array to drop items from.

Supported formats:
  ✓ Array

Count

🎯 The number of items to drop from the beginning.

Supported formats:
  ✓ Number
  ✓ String

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the input before internal logic (e.g., convert object to string, normalize case). Internal transformations such as case handling will still apply afterward.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the result before returning it (e.g., str => str + ' €', val => val !== undefined for boolean conversion). Useful for chaining transformations on the output.

Array To Process array

💡 Type any text to see the result update live

🎯 Using special value — click input to type instead

Test with:

Falsy undefined null "" empty 0 false NaN

Truthy true 42 "hello" {} empty [] empty {a:1} [1,2,3]

Count number

🔗 Result Handling — Chain Variables

Chain apply-mode variables to the output. Each variable receives the result of the previous one.

dropItems()

+ Chain another variable

---

Related Variables

Same category: Array

→ chunk → compact → dropItemsRight → every → filterArray → find → findIndexByCallback → findIndexByRegex → flatten → head → includesAll → includesAny → includesNone → indexOf → join → last → lastIndexOf → reduce → reduceRight → reverse → selectFromArray → some → sort → tail → takeItems → takeItemsRight → uniq → wrapInArray

---

Under the Hood

📜 View Implementation Code

/**
* Removes the first count elements from the array and returns the rest.
* 
* @param {Array} data.src - The array to drop items from.
* @param {number|string} data.cnt - The number of items to drop from the beginning.
* @param {Function|string} [data.out] - Optional output handler: function to transform result or string with format.
*
* Direct-mode specific parameters:
* @param {Function} [data.pre] - Optional pre-processor function to transform src before dropping items.
* 
* @returns {Array} A new array with the first count items removed, or empty array if input is invalid.
*
* @framework ggLowCodeGTMKit
*/
const getType = require('getType');
const makeNumber = require('makeNumber');

const dropItems = function(arr, count) {
   const cnt = makeNumber(count);
   if (getType(arr) !== 'array' || cnt !== cnt || cnt < 0) {
       return [];
   }
   return arr.slice(cnt);
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// dropItems - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(dropItems(value, data.cnt));
// ===============================================================================
// dropItems(...) – Apply Mode
// ===============================================================================
/*
return function(value, count) {
   count = data.rp1 ? data.cnt : count;
   return out(dropItems(value, count));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] Drop first 2 items'
✅ String count parameter - converts to number and drops elements
✅ '[example] Drop all returns empty'
✅ Negative count - returns empty array
✅ Non-array input - returns empty array